Field of the Invention
The disclosure generally relates to the joining of pipe ends. Specifically, the disclosure relates to the joining of pipe have restrictions on relative ovality.
Description of the Related Art
Joining ends of pipe with other pipe or components requires a certain amount of is interface material on the ends to be able to adequately join end to end, typically by welding. A mismatch of the ends is measured through an inside cross-sectional dimension, outside cross-sectional dimension, or wall thickness, and ovality or roundness. FIG. 1 is a schematic illustrating a prior art set of mismatched pipes due to ovality. A first pipe 2 that has been stressed in handling such as on a pipe reel for offshore applications can develop ovality in the circumference. In contrast, a new pipe 4 (or other component) that has not been stressed in the same manner may have the intended circular shape as originally manufactured. Due to certain guidelines and regulations, there is a maximum ovality tolerance for joining the different pipes, depending on the conditions to obtain the structural requirements needed for the joining. If the ovality mismatch between the pipes is too large, then field replacement may not be possible with existing pipe since most if not all of the field pipe has been ovalized on the pipe reel.
A typical ovality issue in offshore installations occurs with reeled pipe, such as coiled pipe. As the reeled pipe is unwound to attach pipe or other components to the end of the reeled pipe, the components are generally welded together. Because the reeled pipe has outside compressive forces that cause ovality, which unreeled pipe or components do not have, then the ovality mismatch can occur at the joint. The ovality tolerances can be important to maintaining structural integrity and reduce fatigue and failure during the normal life of the pipe.
There remains then a need to manage pipe ovality to reduce correction and especially field correction.